NEMA fixture
NEMA fixtures are outdoor lighting fixtures that use a design standard that are set by the N'ational '''E'lectric 'M'anufacturers 'A'ssociation ( NEMA ). NEMA fixtures are produced and distributed by many different manufacturers, including General Electric, Westinghouse, American Electric, among others. History The origin of the NEMA fixture can be traced back to 1941, when every major electrical manufacturer got together to form the NEMA [ National referring to the United States. ]. The point in doing this was to set a standard in certain street lighting ; before this date, every manufacturer had it's own design and standards set. The forming of NEMA meant that certain fixtures that were produced by major manufacturers would follow a certain design standard that assured the configuration or modification of a fixture would be extremely easy. By 1980, the NEMA fixture was the most numerous outdoor lamp fixture in the United States. NEMA fixtures could, and can be found virtually everywhere. The reason for this is because the NEMA fixture assured a long, efficient lifetime for a cheap price. Most NEMA fixtures were sold at lower prices than directly manufacturer-designed fixtures. This meant that poorer and average towns and cities could install multiple fixtures without using too much money. Styles (incomplete) Multiple styles of NEMA heads have been developed since the creation of the fixture in 1941. The wide variety of styles assured a better fit for select streets, both for aesthetic and functional reasons. The only NEMA fixture style that remains popular is the "Bucket" style which has become one of the most numerous street light fixtures in the United States. However, this list is incomplete. Radial Wave Among NEMA's list of different styles of fixtures was the radial-wave luminaire, a fixture that used the "radial-wave" style of many streetlights of it's time. NEMA introduced this fixture in 1941 as one of the first styles developed. Although this was among the first NEMA fixture styles that was conceived, the general idea of radial-wave street lights were not conceived by NEMA, as the radial-wave street lights could be found in the 1910's. The radial wave NEMA fixture used incandescent technology, and was manufactured from 1941 to around 1953. Radial-wave NEMA heads are now extremely rare, if not extinct. Admiral Hat The "admiral hat" NEMA fixture was, unlike the radial-wave style, an idea conceived by NEMA themselves. The fixture consisted of a completely open reflector that could be open and closed by use of a "cap" that protruded from the side of the fixture. When open, the fixture resembled an admiral hat, hence the name of the style. The reason for the completely open reflector was to produce an economic, more affordable option of NEMA fixtures. The admiral hat fixture used either incandescent or mercury-vapor, and was manufactured from around the mid-1940s to the mid-1960s Gumdrop The "gumdrop" NEMA fixture was perhaps the most normal out of all styles. It consisted of five pieces; a spherical, glass half-globe that housed the lightbulb, a metal half-globe above the glass globe, a cylindrical, rounded piece above the metal globe, a small piece above the main structure that housed the photocell, and a connector to the side of the fixture that could be conveniently connected to a mast. Such styles of street lights were common in this time period. The gumdrop NEMA head was manufactured from 1941 to around 1955, and originally used incandescent technology; later, mercury-vapor was used. This is a relatively rare fixture and can be hard to find. A similar style was also manufactured, that will be listed below. Teardrop The "teardrop" NEMA fixture was the same idea as the gumdrop fixture, except that the globe that housed the lightbulb extended further down. This design was created to accommodate and cater to larger streets that required a more extended range of light for increased safety. Like the gumdrop, teardrop NEMA fixtures were not an original design and were common in the time period. This fixture was manufactured from 1942 to around 1955. Bucket The "bucket" was NEMA's most successful fixture that is still manufactured today. This style can be found everywhere in the United States, more commonly in older areas of towns and cities, but still extremely popular nonetheless. It is among the most common and numerous street light fixtures in the United States, having aged very well. It is also quite popular in other countries, as the bucket NEMA fixture is regularly exported due to the cheap price and efficient lifetime. Despite the popularity of this fixture, it is the second-most unique of the NEMA fixtures. No other street light has ever resembled the fixture, making the ubiquitous'' '''''bucket fixture instantly recognizable. This fixture is also used for security and area lighting; smaller versions with the same design are regularly installed on properties above door frames or on wooden poles. Such versions of this fixture can be bought at most home improvement stores and on Amazon. The bucket NEMA fixture was introduced in the early 1960's and can still be purchased today. However, the popularity of this fixture has gone down in recent years. They are now seen as visually unappealing to many, and towns and cities have been making efforts to phase them out. Bucket fixtures are mostly replaced with flat LED heads, with the mast remaining untouched. The bucket NEMA fixture has used mercury-vapor, high-pressure sodium, and metal-halide. Originally, mercury-vapor was used; then, high-pressure sodium bucket fixtures were manufactured. Metal-halide has also been used for this fixture; both high-pressure sodium and the latter are still manufactured to this day. Masts (Bucket-Only) NEMA manufactured different styles of masts to use with NEMA fixtures. These masts were designed to accommodate with different locations and the placement of the street light, with the size ranging from shortl to long. Apart from the functional purpose of making different masts, a reason for this was also for aesthetic and variety. Long Arm Double-Guy Mast The longest NEMA mast consists of a basic "arm" mast, and two thin wires connected from the pole to the mast. The wires were for extra support; additionally, for a direct source of electricity from the pole to the fixture ( as opposed to hiding the wire inside the mast ). This mast was designed for long range of light when needed. It can commonly be found on smaller roads and entrances to residential zones or parking lots. Long Double-Mast A more conventional long-scale version of the NEMA mast, this style consists of two, basic long masts with two bars connecting both masts with each other. Unlike the double-guy mast, this style is more common and can be found in a wider range of places, including most roads. Medium Double-Mast The most common style of NEMA masts for street lighting is the medium-scale version. This can be found on most roadways and entrances to parking lots. The reason for this being the more popular NEMA mast is probably due to the fact that it's medium size means that it will accommodate and cater to a wider range of places. Multiple versions of this mast were made with minor differences. It consists of one curved mast, and a straight mast below, along with a single bar to connect eachother. Short Mast The short mast variation of the NEMA masts is only used for one-lane roads and area and security lighting. It is very simple in design and only consists of a basic pole with a curve. The mast includes a piece at the end of the curve that can be easily, but firmly attached to wooden poles. There are multiple variations of this mast that have been produced. References * https://streets.mn/2016/07/15/the-overhead-streetlights-of-local-streets-part-1/ Category:1940s Category:Miscellaneous